Ozone effectively oxidizes a variety of water borne contaminants without leaving an undesirable residual, adding to total dissolved solids (TDS) levels or causing radical shifts in pH. Ozone is used to achieve a number of water treatment goals, including disinfection and oxidation of both inorganic and organic contaminants. Ozone is also an effective pretreatment for improving the performance of subsequent water treatment processes.

Disinfection

Broadly defined as the inactivation of bacteria, viruses and parasites, ozone very effectively eliminates many of these contaminants. E. Coli, Staphylococcus, Legionella pneumophila, the protozoa Giardia and Cryptosporidium are examples of microorganisms that are oxidizable by ozone.

Oxidation of Inorganics

Ozone is commonly used to remove ferrous compounds and manganese from water. The problems normally associated with the presence of these metals are more aesthetic than health related. However, standards have been established for both in their soluble states because the growth of iron- and manganese-oxidizing bacteria can cause a deterioration overall water quality.

Oxidation of Organics

Ozone can be used to treat color, taste and odor problems normally caused by the presence of organic materials in water. The primary cause in natural waters is humic substances (decomposed plant and animal matter) and while such removal methods as ion exchange or microfiltration are effective, ozone is the most efficient of the oxidizers in performing this function. In situations where ozone is being utilized for color removal, it can perform the added function of killing bacteria if traditional methods are ineffective due to bacterial fouling.

Hydrogen sulfide, iron, copper and zinc are notable inorganic tastes and/or odor culprits, while the responsible organics are often algae compounds. The treatment process depends on the type of compound causing the problem, but usually involves at least one oxidative stage (ozone, chlorine, potassium permanganate, etc.) followed by a non-oxidative stage (activated carbon, sand filtration, etc.).

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